Teores de mercúrio em cabelo e consumo de pescado de comunidades ribeirinhas na Amazônia brasileira, região do Tapajós

Chronic Methylmercury Intoxication Induces Systemic Inflammation, Behavioral, and Hippocampal Amino Acid Changes in C57BL6J Adult Mice

Methylmercury (MeHg) is highly toxic to the human brain. Although much is known about MeHg neurotoxic effects, less is known about how chronic MeHg affects hippocampal amino acids and other neurochemical markers in adult mice. In this study, we evaluated the MeHg effects on systemic lipids and inflammation, hippocampal oxidative stress, amino acid levels, neuroinflammation, and behavior in adult male mice. Challenged mice received MeHg in drinking water (2 mg/L) for 30 days. We assessed weight gain, total plasma cholesterol (TC), triglycerides (TG), endotoxin, and TNF levels. Hippocampal myeloperoxidase (MPO), malondialdehyde (MDA), acetylcholinesterase (AChE), amino acid levels, and cytokine transcripts were evaluated. Mice underwent open field, object recognition, Y, and Barnes maze tests. MeHg-intoxicated mice had higher weight gain and increased the TG and TC plasma levels. Elevated circulating TNF and LPS confirmed systemic inflammation. Higher levels of MPO and MDA and a reduction in IL-4 transcripts were found in the hippocampus. MeHg-intoxication led to increased GABA and glycine, reduced hippocampal taurine levels, delayed acquisition in the Barnes maze, and poor locomotor activity. No significant changes were found in AChE activity and object recognition. Altogether, our findings highlight chronic MeHg-induced effects that may have long-term mental health consequences in prolonged exposed human populations.

Exposição ao mercúrio e anemia em crianças e adolescentes de seis comunidades da Amazônia Brasileira

Resumo O mercúrio (Hg) é uma substância tóxica, sendo o consumo de pescados uma das principais fontes de exposição da população. Este artigo visa avaliar a associação entre anemia e exposição ao Hg na população infanto-juvenil de seis comunidades ribeirinhas da Amazônia Brasileira. Realizou-se a análise secundária de dados de estudos seccionais, incluindo 1.318 indivíduos, divididos em dois grupos segundo a influência do garimpo (grupo A sob influência, e grupo B sem influência). Métodos de análise multivariada foram realizados para verificar a associação entre variável de exposição (Hg no cabelo) e anemia, estratificando pelos grupos. Foram observados 348 casos de anemia (27,1%), sendo 206 entre o grupo B e 142 no grupo A. Houve diferença na mediana dos níveis de Hg entre os grupos (A = 12,8µg/g e B = 4,3µg/g, p = 0,01). Foi observada associação entre Hg no cabelo ≥ 6,0µg/g e anemia (OR = 1,38; IC95% = 1,02-1,87), fato que foi magnificado para o grupo A quando realizada estratificação (OR = 2,23; IC95% = 1,28-3,90). O estudo mostrou elevados níveis de Hg, principalmente no grupo A, e que essa substância pode ser um possível fator de risco para anemia. Além disso, as áreas geográficas pareceram modificar esse efeito, apontando para influência de outros fatores, fato que deve ser melhor avaliado.

Sexual and reproductive health in riverine communities: integrative review

OBJECTIVE

To analyze the scientific evidence available on the sexual and reproductive health of riverine communities.

METHOD

Integrative review, conducted on the databases LILACS, MEDLINE; WEB OF SCIENCE and SCOPUS, including publications in Portuguese, English or Spanish, without an initial time limit and published until 2018.

RESULTS

11 studies were selected. The studies included are from the period 1993-2017. The results originated four analytical categories: sexual component, which gathered findings about sexually transmitted infections; reproductive component, which included family planning/fertility control, abortion and problems with pregnancy; environmental component, which presented issues with environmental contaminants and its reproductive implications; and the sociocultural component, which discussed gender, beliefs and social indicators.

CONCLUSION

In this review, studies with a quantitative approach, from a female point of view and a biological perspective predominated. No study investigated the meanings and representations of SRH for the riverine communities. In addition, the findings show little evidence of thoughts and practices of people living in riverine communities regarding SRH issues, providing limited evidence.

Toxic and essential trace element concentrations in fish species in the Lower Amazon, Brazil

The Lower Amazon region (Western Pará, northern Brazil) is greatly affected by mining exploitations (particularly artisanal gold mines) and other industrial and intensive agricultural activities with potentially strong impacts on aquatic ecosystems. Although such impacts include contamination with various toxic elements, to date only the effects of Hg have been considered. In this study, toxic and trace element concentrations were determined in the flesh of 351 fish specimens, including detritivores (Acarí, Pterygoplichthys pardalis), omnivores (Piranha, Pygocentrus nattereri; Pirarucu, Arapaima sp.) and carnivores (Caparari, Pseudoplatystoma fasciatum; Tucunaré, Cichla ocellaris), during the dry and wet seasons in 2015 and 2016. The range of concentrations of toxic element residues were 2-238 μg/kg fresh weight for As, 1-77 μg/kg for Cd, 4-1922 μg/kg for Hg and 1-30 μg/kg for Pb. Only the maximum concentrations of Hg established in the Brazilian legislation for fish destined for human consumption (0.5 mg/kg) were exceeded (in 16% of carnivorous species). The large between-species and seasonal differences observed for all these toxic elements are probably related to the seasonal behaviour and dietary habits of the different fish species. By contrast, essential trace element concentrations were low and not related to seasonal or dietary factors, and the observed differences may be at least partly related to the metabolism of each species. The associations between Hg and the essential trace elements Se, Fe, Co and Mn deserve special attention, as these trace elements may play a role in Hg cycling and methylation and merit further evaluation with the aim of reducing Hg toxicity in aquatic environments.

Factors Associated with High Mercury Levels in Women and Girls from The Mojana Region, Colombia, 2013-2015

Women are primarily exposed to mercury through the consumption of fish contaminated by gold mining activities. The main systems affected are the central nervous and renal systems, although effects on the reproductive system have also been found. Objective: To explore the relationship between mercury levels in women and their possible sources of contamination. A cross-sectional study was conducted from 2013 to 2015 with women residing in 11 municipalities in La Mojana, Colombia, using non-random sampling. Standardized instruments were used to identify sociodemographic characteristics, mercury use, mining-related activities, water and fish consumption, and other factors. Blood, urine, and hair samples were taken to quantify mercury levels. A logistic regression model was used to identify factors associated with elevated mercury values in the participants’ samples. A total of 428 women were included, with an average age of 36.7 ± 16.7 years, 3.3% of whom were pregnant at the time of the survey and 8.4% of whom were exposed occupationally. High levels of mercury were present in 62.8% of the women, in any one of the three samples processed. Those exposed occupationally and environmentally had similar values (p = 0.821). Frequency of fish consumption and source of drinking water were associated with higher levels of mercury (p < 0.05).